The systematic survey of microbial species for the presence of siderochromes (high affinity iron carriers), which are of possible use in the treatment of Cooley's anemia and iron storage disease, will be extended through the blue-green algae and the enteric bacteria. A specific siderochrome, apparently related to schizokinen, formed by an Anabaena sp. growing at low iron will be isolated and characterized. The hydroxamate type siderochromes produced by Enterobacter aerogenes, Enterobacter cloacae, and Klebsiella pneumoniae, will be identified. Organic synthetic methods will be perfected for the synthesis of both catechol and hydroxamate type siderochromes. The ability of siderochromes to remove iron from mammalian ferri-proteins, such as iron transferrin, ferritin, and hemosiderin, will be determined.